Matthew Grimshaw
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Matthew Grimshaw

Matt Grimshaw — known as Coach Grimmy — is the founder of SISU Fitness, a HYROX-affiliated gym coaching athletes from first-timers to world podium contenders. He blends functional fitness science with SISU grit to help you train, race, and perform at your best.

Group of athletes cheering each other through the last few wall balls
The SISU Mentality: How to Stay in the Fight When It Hurts

The SISU Mentality: How to Stay in the Fight When It Hurts

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Athletes performing sled pushes, carries, and burpees in a gritty gym — chalk in the air, focused intensity, and a coach motivating in the background
Why Functional Fitness Beats Fancy Programming

Why Functional Fitness Beats Fancy Programming

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Athlete mid-HYROX race, grit and focus on their face, pushing a sled across the floor surrounded by cheering crowd — captured under bright competition lighting with energy and intensity
How to Pace Every HYROX Station (and Avoid Blowing Up Mid-Race)

How to Pace Every HYROX Station (and Avoid Blowing Up Mid-Race)

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Athlete standing at the HYROX start line, nervous but focused, surrounded by competitors — bright lights, race banners, energy and anticipation in the air
From Couch to HYROX: Your Complete Beginner’s Guide to Race-Day Success

From Couch to HYROX: Your Complete Beginner’s Guide to Race-Day Success

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